We need to find the slope of the line that passes through the points ( 10 , 5 ) and ( 6 , 12 )
The general form of the equation of the line is:

Where m is the slope and b is the y - intercept
The slope will be calculated as following:
Slope = Rise/Run
Rise = the difference of y - coordinates = 12 - 5 = 7
Run = the difference of x - coordinates = 6 - 10 = -4
so, the slope m is:

so, the equation will be :

Use one of the given points to find the value of b
So, using the point ( 10 , 5 )
when x = 10 , y = 5
so,